The invention relates to a method and an apparatus for connecting components, such as pipes, rods and similar semi-finished products, by friction welding, in particular for connecting pipes while drilling deep holes and/or for completing holes, for example cavern holes.
DE-A 20 20 121 discloses a method for connecting vertically aligned pipe sections, in which at least one end of the pipe sections to be connected is provided with a chamfer, which acts as a welding joint. A plurality of weld layers are introduced, with the aid of a welding apparatus, into the welding joint formed in this way, in order to connect the components to one another. The welding apparatus comprises a bracket which is mounted on one of the pipe sections to be connected, coaxially with respect to their common longitudinal axis, and a welding head which can be moved on a circular path along the outer casing of the pipe sections to be connected in order to introduce a weld metal into the welding joint, supported and held on the bracket. The welding head is furthermore equipped with means in order to move its horizontal position radially with respect to the external diameter of the pipe sections to be connected.
The solution according to DE-A 20 20 121, which, subject to certain preconditions, appears to be usable on site for the production of pipe systems in deep holes, is very complex from the installation point of view and with respect to the envisaged method technology since a weld filler which can be liquefied must always be used for securely connecting the pipe sections, and a number of weld layers must be incorporated into the welding joint. Furthermore, the setting up and alignment of the welding apparatus involves a further time penalty.
A so-called radial friction welding method, which is improved in comparison with the solution mentioned above, for connecting tubing and casing pipes is disclosed in GB Patent Application 8910118.2.